Wherein we ponder vexing issues in infection prevention and control, inside and outside the hospital.

Sunday, September 26, 2010

My new VAP definition is unstoppable!

As we have blogged on numerous occasions, existing ventilator-associated pneumonia (VAP) definitions (for both clinical and surveillance purposes) are craptastic. In Mike’s recent post about this problem, he calls for CDC to collaborate with IPs and hospital epidemiologists to help develop better definitions. Well, the CDC is doing just that. They have been working with critical care and ID physicians, as well as with some of the CDC Epicenters, to develop and assess a new definition for “VALORI” (Ventilator Associated Lower Respiratory Infection). A simple algorithmic summary of the approach is below, courtesy of Dr. Shelley Magill, who gave an excellent talk at a recent CDC/HHS meeting I attended in DC:

The major objection voiced to the draft VALORI definition is that by removing some aspects that introduce subjectivity, the definition becomes more of a severity of illness measure than a description of what we know clinically to be VAP. The definition also retains some elements that are subjective (or hinge on clinician behavior, such as use of antibiotics), so it isn’t clear if it will have better performance characteristics than the current NHSN definitions.

In my view, we should not use VAP as a quality measure, period. VAP rates should not be compared across hospitals, publicly disclosed, or used in any pay-for-performance schemes. For as soon as they are, hospitals will quickly learn to reduce their rates without doing anything that actually improves patient outcomes (e.g. by narrowly interpreting clinical signs or CXR findings, by seeking consensus among multiple IPs for each case, or by incorporating clinician’s opinions regarding the diagnosis).

In the meantime, we can probably agree on some practices that could be selected for public reporting and benchmarking (i.e. process measures). The practices chosen should be those that are demonstrated to improve meaningful patient outcomes in controlled clinical trials. A great example is this 4-center study of spontaneous awakening + spontaneous breathing trials. The investigators, recognizing the futility of defining VAP, instead demonstrated reductions in ICU days, vent days, hospital days, and mortality in the intervention group.